Integrated circuits generally include logic blocks that are used to implement a wide variety of functions including image processing algorithms, allowing the integrated circuits to be used in video processing applications such as video surveillance and other video systems.
Integrated circuit devices in video processing systems typically include video processing circuitry for processing video data. In some scenarios, the video processing circuitry can be used to process interlaced video data. As is well known, an interlaced video or image contains two fields of pixel lines such as a field displaying the odd numbered rows and another field displaying the even numbered rows of a frame of interlaced video data. The frame needs to be converted to a non-interlaced format (a “deinterlaced” format) prior to being displayed on display equipment such as a progressive scan monitor.
Some conventional image processing devices deinterlace the interlaced video data by interpolating pixel values for missing rows of pixels in one of the fields using pixel values located immediately above and immediately below the pixel to be interpolated in the video field. However, when the video data contains low-angle edges (i.e., edges having an angle relative to horizontal of less than 45 degrees and greater than −45 degrees), the video field may include insufficient data to properly resolve the low-angle edges when interpolating the pixel values. Performing interpolation in this manner can generate erroneous interpolated pixel values and deinterlaced video data that contains noticeable image artifacts.